1. Field of the Invention
The present invention relates to a read apparatus for an RF tag, and more particularly relates to a redundancy in a read apparatus for an RF tag and a controlling method for the same.
2. Description of the Related Art
An RF (Radio Frequency) tag reader/writer apparatus can perform a radio communication with an RF tag and read ID (Radio Frequency Identification) of the RF tag. As for a trouble of the RF tag reader/writer apparatus, it may be considered to use two or more RF tag reader/writer apparatuses and ensure its redundancy. However, if the two RF tag reader/writer apparatuses are installed separately from each other, there is a problem which of the RF tag reader/writer apparatuses is used when the ID of the RF tag is read. If they are installed close to each other, there is a possibility of interference of an electric wave.
In conjunction with the above description, Japanese Laid Open Patent Application (JP-P2005-157645A: first conventional example) discloses a read apparatus. In this conventional example, the read apparatus for a radio tag in which an identification code is recorded without any contact. This read apparatus includes a plurality of reader apparatuses to which a plurality of antennas are connected. A controller performs a control in which one antenna connected to each reader apparatus is turned on when a plurality of tags are located at a read region of the read apparatus. Thus, the adjacent antenna is not turned on, and the plurality of radio tags inside the read region are consequently read.
Also, Japanese Laid Open Patent Application (JP-P2005-339089A: second conventional example) discloses a non-contact ID system. This conventional non-contact ID system includes a plurality of answerers, a questioner and a host manager. The plurality of answerers store peculiar identifiers, and meet communication standard different from each other. The questioner contains a plurality of signal processing sections and a control section. The plurality of signal processing sections send a plurality of question signals are transferred to the answerers based on the respective communication standards. The signal processing section contains a plurality of signal processors, each of which receives the answering signal including the identifier replied by the answerer receiving the question signal of the communication rule agreeing with itself. When receiving the external question request, the controller outputs a drive command or stop command to its signal processor. The high order manager outputs the question request to send the question signal based on any of the communication rules to the answerer.
When sending the question signal based on any of the communication standards to the questioner, the host manager sends a question request corresponding to the communication rule. Then, the controller of the questioner outputs the drive command to the signal processor corresponding to the communication rule. On the other hand, the controller outputs the stop command to the signal processors corresponding to the communication rules except it. This non-contact ID system has such feature.